BoilerFaultCodesYour boiler is trying to light itself to provide heat, but it is failing to create a flame, likely because it is not getting enough gas or the spark isn't catching.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Failure during start-up: Ignition unsuccessful
What causes this fault?
This fault occurs when your boiler attempts to fire up but cannot detect a stable flame after several attempts. The most common reasons are a lack of gas reaching the unit, a worn-out spark plug that cannot ignite the fuel, or a internal sensor that is too dirty to 'see' the flame correctly.
In freezing temperatures, this code can be triggered if your external gas meter regulator or condensate pipe freezes, physically blocking the boiler's ability to operate.
DIY fix possible
Check that your gas emergency control valve is open and any prepay meters have credit.Verify if other gas appliances in your home, like a hob, are working correctly.If it is freezing outside, check if your condensate pipe (the plastic pipe leading outside) is frozen and thaw it with warm water.Press the Reset button (the flame symbol with a cross) for one second.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F.28 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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